Just got my first 40 S&W, any load suggestions?

[rolltide]

I just bought my first 40S&W. It is an AMT Backup. (OK, stop laughing, it is not THAT funny.) Most of what I had heard about the pistol was not favorable, but for an all stainless gun about the same size as the Kahr PM40 (only with larger grips that fit my long fingers better than the Kahr) and with a price tag of $175 and a 30 day guarantee from a reputable gun shop, I thought I could not go to far wrong. I put most of a box of 180 JHP through it today. I had one Fail to Feed which quickly righted itself with a rack on the slide and one light primer strike. The gun is typical AMT fit and finish, so I figure a little ramp polish will fix the FTF. I also figure a new set of springs might be in order since it looks like it has been fired a lot. Overall though, I would have to say that the little 40 is quite accurate and has not lived up to all the bad press about being a jam-o-matic and a heavy recoiling pain to shoot. Multiple shots were actually quite fast and quite comfortable (much better than most 38 snubnoses I have fired.)

Does anyone know where to get a set of springs and/or does anyone have any suggestions for a load to carry in this short barrel 40?

Thanks,

Roll Tide

 

[wally]

AMT is Belly Up so if www.gunsprings.com doesn't have what you need it could be tough.

I have the two AMT backup .380 models one SA the other DAO and the DAO .45.

Two out of three needed a little work to be reliable.

I put a few #4 (if I remember correctly) washers under the 45 Backup mainspring to solve the light primer strike problem it was having. Was one of my main carry guns for years until I got a Kahr PM40 and Kimber Ultra Carry.

AMTs that work are nice, but too many didn't. They are a very nice size for their caliber but too heavy to carry without a belt IMHO.

For a starting load try 6.0 gr Unique and a 180 gr bullet shoots well for me, Allaint lists 6.4 gr as MAX, I made some with 6.3 and they were hotter than I like in used brass . I like heavy bullets cause you need all the penetration you can get with a small gun.

I'd buy the .40 at that price just to complete the set

--wally

 

[rolltide]

Wally,
Thanks for the info. I will try the washers on the main spring idea. Do you have any suggestions for factory ammo to carry in the gun. I have nothing else in 40 caliber, so I have never really looked closely at loads in that caliber. Gunsprings.com has recoil springs for the 45 DAO Backup, would those work on the 40 as well? They also have other springs for the 380 Backup, but I don't know if main springs, firing pin springs, etc. will interchange with other calibers.

The same store has a AMT Backup in 38 Super at the same price if you are interested. I had never seen one in that caliber before. They both were traded in by the same guy.

Thanks again for your help.

Roll Tide

 

[CB900F]

Rolltide;

Check & see if the AMT gives you a fully supported chamber or not. Not means the feed ramp extends into the chamber area. Just stuff an empty brass in the barrel, after disassembly & check to see if anything in front of the extracter groove is visible. If so, you do not have a fully supported chamber & don't want to load hot or shoot the hottest factory ammo you can find.

Just my .02.

900F

 

[cratz2]

As suggestions for loads to try, I'd give 165 Gr Gold Dots and 165 Gr Golden Sabers a shot. They are two of the best loads for serious use and I've always found the Golden Sabers to be very reliable feeders in most guns.

Based on other's experience, I'd try to get any replacement springs ordered ASAP and try a few different loads to see if it can be made reliable. If you can make it reliable, it should be a pretty nice small gun for $175.

 

[rolltide]

Thanks for the heads up on the ammo. This gun is amazingly simple. I believe that short of a frame, slide, or barrel, I could fashion most any part myself if I needed to. I think there are only 32 parts in the entire gun including 4 in the magazine. If I had to own one gun for which no factory parts were available, this would be the one. I am going to run a few boxes of the 165gr rounds through it. If it proves reliable with that load, I am going to use the "if it aint broke don't fix it" rule. If I continue to get light strikes, I am going to use wally's fix for that.

Thanks guys!

 

[twowheel]

I use Vihtavordi N340 and Alliant Powerpistol powders for all my 40 S&W loads. Weight of powder will vary depending upon the bullet type, make and weight. With 155 gr Rainer I use 6.5 gr N340.

Your mileage may vary.

Check the Alliant web site for their info.

Twowheel

 

[wally]

I like 180 gr Hydra-shok or 180 gr Golder Sabers in my Kahr PM40.

I used 230 gr Hydra-shok in the Backup 45 when I carried it.

I'm not intrested in .38 super guns.

--wally.

 

[Cal40]

Load

I load for my Kahr P40 for several years and my preference so far is 4.0 gr of Bullseye, pushing a 165 gr Montana Gold bullet.

I am thinking really hard about trading off the P40 for a PM40 for CCW.

 

[rolltide]

Well, after polishing the feed ramp, a thorough cleaning and ordering a few new mags, I have wrung out the AMT 40S&W Backup to my satisfaction. I have fired Cor-Bon PowerBall 135gr, UMC 180gr JHP, Fed 165gr JHP, PMC 165gr FMJ-FP. The gun now functions 100% with all these rounds. Interestingly, all rounds seem to hit at the same point of impact, which is good since the only sight is a "gutter sight". I did some VERY informal expansion and penetration tests in a clay bank. The PowerBall was awesome. It blew a 2 or 3 inch diameter hole into the clay bank. I thought I had fired a shotgun when all the dirt came raining down after being blown into the sky. I have decided to carry the Cor-Bon PowerBall round because:

1. It is a light fast round that should retain plenty of velocity from the 3" barrel.

2. The polymer ball in the hollow point removes any doubt of reliable feeding.

3. The polymer ball also insures expansion regardless of what material is encountered.

4. The Cor-bon load has a groove rolled around the middle of the case which should help prevent any bullet setback in rounds from being cycled. This is crucial since the 40S&W operates at such high pressure anyway.

The little AMT Backup will shoot 3" groups from 30 feet, off hand, if I do my part. That accuracy exceeded all my expectations of a 3" barrel in a powerful round. It is difficult to shoot the Backup well since the trigger is so heavy, and would be a real challenge for someone with small and/or weak hands, but overall, I think it is a keeper. By the way, the 2 new OEM magazines I got were both jammo-matics. I think the mags may have been the source of much of the bad press on these guns. The mag lips were spread to far. A little adjustment and they are now 100% reliable.

I just got my 357sig barrel in the mail. I can't wait to get some ammo and wring it out.

The AMT is not quite as concealable as my NAA Guardian, but it is a close second and is much more powerful. It will slip in and out of a front pocket with ease. It is in the same power range as my 357 and 45, only in a much smaller package.

I like it!!!!!!!!!!!!!!!

 

[cratz2]

Hey... if it's reliable with ammo that you like, I think you got yourself a screamin deal on a nice small carry gun.

 

[rolltide]

cratz2,
My local gun shop told me that most of the county sherrif's deputies buy the Gold Dots and Golden Sabers, just like you suggested. He said the county coroner also said that the PMC Starfires were particularly effective. I wanted to quanity test different rounds for reliability, so I could not afford to buy that 20 round box stuff. I had to buy stuff that was a reasonable price in a 50 round box. My local gun shop gave me a special deal on the Cor-Bon stuff, so I tried that. I want to try some of the other rounds that you suggested, I just did not have enough money to do a 200 round reliability test with that ammo. I have found a round that I am comfortable carrying and shooting. I hope to try some of those more expensive rounds later.

Roll Tide